Added TLS1.2 support - may need installer edits for .NET 4.6.2

[johncdoherty]

• Re-targeted all the projects to .NET Framework 4.6.2 to provide TLS1.2 support
  • Most code changes included are auto-generated due to this re-targeting
• Made solution work with Visual Studio 2015 (2010 doesn’t support >.NET 4.0)
  • Updated readme accordingly
• Made ActiveReports references not be version-specific
• Added the following to the AppLogisticsApp::App.xaml.cs and AppLogisticsPlugin::Mailer.cs to force TLS1.2 (since some machines might still be configured for different security)

ServicePointManager.Expect100Continue = true;
ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;

• Retested in Fiddler and verified all initial connections utilize TLS 1.2